Conceptually, the ability to track the location of individuals within the confines of a building or other confined spaces is rather simple. The basic premise is to have a transmit device on all personnel and a centralized receiver at a control center. Though simple in concept, implementation has proven elusive. Typically, such transmit devices are radio transmitters that are worn by the user and the user may initiate communication with a push of a button (i.e., push-to-talk). However, this requires that the user must engage the transmitter button to contact the control center. To overcome this problem, the radio transmitter may, in one aspect, be an automatic mode wherein the transmitter is continuously transmitting. However, these transmitters typically operate on the same frequency and, thus, multiple transmitters continuously transmitting may interfere with each other.
Thus, a problem in locating one or more individuals within a building requires that the individuals have a method of generating one or more signals that can uniquely identify each individual and determine their location from the transmitted signals without hindering or requiring operation by the user.
Hence, there is a need for a lightweight transmitter/receiver configuration for providing unique identification of a transmitting source and monitoring, tracking and locating the transmission.